Chapter 3. LED Basics

LEDs come in a number of shapes and forms (including the organic LED and polymer LED), but the basic LED is a semiconductor. They are small, long-lasting, and power efficient. They are made of a semiconductor material in order to produce the desired color tones.

How LED works is not particularly complex from a scientific point of view, but it’s quite far removed from the purchase and usage of LED lighting. Lots of information is available if you’d like to dig deeper into the physics and chemistry behind semiconductors, but it should suffice to say that an LED is a diode—a device that allows electricity to pass through it in a single direction—that emits light. That light can range from infrared (non-visible) through the color spectrum, depending on the semiconductor material that is used. For example, a red LED might use aluminium gallium indium phosphide (AlInGaP) and a particular voltage drop (from one side of the diode to the other) to emit the desired color.

White light is the combination of all of the colors in the visible spectrum. Because of this it can result in a number of shades, and producing it is not as easy as just using a particular semiconductor material. There are a number of different methods for producing white light, some of which are more energy efficient than others, and some methods are patented by particular companies. Once you factor in this information and secondary facts, such as the blue LED light is cheaper to produce than white light, ...

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